High speed single vane motor

ABSTRACT

A single vane motor, for work extraction from the expansion of compressible fluids, comprised of three basic units, a single rotating vane mounted on an output shaft comprising a first rotor, a stationary housing and end plates, a rotating drum, comprising a second rotor, mounted on bearings in the housing, on an axis offset from the axis of the first rotor. A predetermined volume of working fluid is admitted into the cylindrical chamber provided by the housing on each revolution. The pressure of the expanding fluid acts directly on the vane to transmit torque to the shaft, the expansion providing an ever increasing volume behind the vane until an exhaust port is uncovered.

United States Patent [191 Cartland et al.

HIGH SPEED SINGLE VANE MOTOR Inventors: William H. Cartland, Jupiter; Ernest R. Earnest, Hobe Sound, both of Fla.

Filed: Mar. 6, 1972 Appl. No.: 231,892

References Cited UNITED STATES PATENTS 11/1873 Myers 418/138 10/1903 Patschke 418/138 X 4/1894 Nadeniczek 418/138 X Oct. 9, 1973 Primary ExaminerCarlton R. Croyle Assistant ExaminerRichard Sher Attorney-John Cyril Malloy [5 7 ABSTRACT A single vane motor, for work extraction from the expansion of compressible fluids, comprised of three basic units, a single rotating vane mounted on an output shaft comprising a first rotor, a stationary housing and end plates, a rotating drum, comprising a second rotor, mounted on bearings in the housing, on an axis offset from the axis of the first rotor. A predetermined volume of working fluid is admitted into the cylindrical chamber provided by the housing on each revolution. The pressure of the expanding fluid acts directly on the vane to transmit torque to the shaft, the expansion providing an ever increasing volume behind the vane until an exhaust port is uncovered.

8 Claims, 5 Drawing Figures HIGH SPEED SINGLE VANE MOTOR BACKGROUND OF THE PRESENT INVENTION In the present invention the torque producing single vane is mounted directly on the output shaft. This is unlike most vane motors in which the torque producing vane load must be transmitted to a rotating drum which is connected to the output shaft. The single vane design therefore has the advantage of reduced friction and wear on the vane sliding seals.

The single vane is mounted directly on the output shaft and thereby positively located and restrained. It is therefore possible to run very close clearance between the vane tip and the housing. In most vane motors the vanes are thrown out by centrifugal force to rub on the housing. The rubbing velocity .limits the speed of such a vane motor. The single vane motor of the instant invention is not speed limited by rubbing. It is therefore less dependent on the lubricating qualities of the working fluid. The only rubbing occurs between the vane and the seal blocks and this is relatively low velocity rubbing.

The single vane motor is self-valving. The rotor drum acts as a valve on the inlet port. This provides the simplest possible arrangement requiring no moving parts other than the rotors. No clearance volume for an inlet valve is required so that the charging volume in the rotor drum can be as small or as large as desired. A small charging volume permits the motor to be built with a high expansion ratio which in turn permits high efficiencies with high pressure ratios. The exhaust port of the single vane motor is always open so that the working fluid is never compressed by the vane during the exhaust cycle. This feature avoids the possibility of damage due to hydrostatic lock should some of the working fluid condense inside the motor.

Because the single vane motor is designed to run at high rotating speeds, it can approach the concept of a turbine as far as fluid dynamics are concerned. That is, some of the energy conversion from the working fluid is accomplished through changes of momentum as well as from pressure acting on area over a distance traveled. The incoming fluid is accelerated in the inlet port to match the tangential'velocity of the rotor thereby dropping the static pressure. As the fluid expands, only that portion which is following the vane must match the rotor tangential velocity while the mean velocity of all the fluid particles is only one half the rotor velocity. Some of the loss in total to static pressure is thereby recovered. This is a unique feature of a single vane machine because in multi-vane machines the body of fluid trapped between two vanes must travel at rotor tangential velocity throughout the expansion cycle. All the kinetic energy must then be lost out the exhaust port. It is desirable to operate at high rotating speeds for two reasons. First, the static pressures inside the motor are lower thereby reducing leakage losses. Second, higher work per unit volume and per unit weight of motor is possible.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal, sectional view through the high speed single vane motor of the present invention;

FIG. 2 is a vertical cross sectional view taken along line 22 in FIG. 1; and

FIGS. 3, 4 and 5 are schematic sectional views, similar to FIG. 2, illustrating the sequence of operation of the motor.

DETAILED DESCRIPTION OF DRAWINGS With reference to the drawings, in which like reference numerals designate like or similar parts throughout the various views, and with particular reference to FIGS. 1 and 2, the numeral 10 designates the single vane motor of the present invention which is generally comprised of a first rotor assembly 12, journaled in opposed end bearings 14 and 16 in a housing 18 and a second rotor 20 comprising a rotating drum 22 having its opposed ends journaled in bearings 24 and 26 in the housing 18.

As further illustrated in FIGS. 1 and 2, the first rotor assembly includes an output shaft 28 and a radially extending vane 30 having a tubular portion 32 at its inner end keyed at 34 to the output shaft 28. The output shaft and vane 28 and 30 rotate about the axis A-A" and the vane 30 sweeps the bore 36 of the main housing member 38, said bore being closed by a pair of opposed housing end plates 40 and 42 which carry the bearings 14 and 16 and are bolted to the main housing member 38 as at 44.

The drum 22 comprising the second rotor 20 is provided with reduced diameter, opposed end portions 46 and 48 which are journaled in the bearings 24 and 26, carried in the end plates 40 and 42. As seen in FIG. 1, the drum is rotatable on the axis BB which is offset relative to axis AA" of the first rotor 12, and drum 22 has a through opening 50, through which the output shaft 28 extends and in which the tubular portion 32 of the vane 30 is held in fixed relation to the output shaft 28.

A longitudinal slot 52 is formed in the drum wall 22 to provide for the outward radial extension of the vane 30 and a pair of semi-spherical, swivel, seal blocks 54 and 56 are inset in the slot 52 to seal the side edges of the slot relative to the respective side faces of the vane 30. The outer cylindrical face 58 of the drum wall 22 is provided with a relieved area or depression 60 and the main housing member 38 includes an inlet port 62 and an exhaust port 64, spaced circumferentially, a substantial distance therefrom in the direction of operation of the rotors l2 and 20.

The rotors l2 and 20 are designed to operate in close proximity to, but not touching, the housing bore 36 or end plates 40 and 42. Labyrinth type seals 66, 68 and 70 are machined respectively into the tip of the vane 30, the opposed end portions of the rotor drum face 58 and in the housing between the inlet and exhaust ports to minimize theleakage of fluid from high pressure to low pressure areas. The rotors operate at high rotating speeds so that the time available for the high pressure fluid to leak past the seals is very short.

In operation and with reference to FIG. 3, a compressed fluid is introduced into the inlet port 62, as indicated by the arrow 76, and into the depression 60, once per revolution causing rotation in a clockwise direction by both rotors l2 and 20, as indicated by the arrow 78.

Further rotation of the rotors l2 and 20, FIG. 4, seals off the inlet port 62 and the working fluid expands into an ever increasing volume behind the vane 30 until the exhaust port is uncovered as illustrated in FIG. 5. The pressure of the expanding fluid acts directly on the vane 30 to transmit torque to the output shaft and each time the depression is moved into realignment with the inlet port 62 and receives a new charge of working fluid, the rotors l2 and 20 make one complete cycle as above described.

it will be obvious to those skilled in the art that various changes and modifications can be made in the single vane motor as illustrated and above described without departing from the true spirit of the invention as defined in the appended claims.

What is claimed is:

l. A single vane motor for work extraction from the expansion of compressible fluids comprising,

A. an enclosed housing providing,

1. an inner bore;

B. a first rotor, rotatably mounted within said inner bore comprised of,

1. an output shaft journaled in said housing and spanning said bore,

2. a vane fixed to said output shaft, within said bore, and extending radially outwardly into close proximity to the inner walls of said housing;

C. a second rotor in the form of an annular drum, to-

tatably mounted within said housing bore on an axis offset from and parallel to the first rotor axis and providing,

1. a longitudinal through opening providing for passage therethrough of said output shaft,

2. a longitudinal slot through the wall of said drum, providing for the radial extension therethrough of said vane and relative movement between said vane and drum,

3. a depression having a predetermined size located closely upstream of the longitudinal slot;

D. circumferentially spaced apart inlet and exhaust ports extending through the wall of said enclosed housing said bore provides an inner wall, the major portion of which is coaxial with said first rotor and a minor portion extending between said exhaust port and a line somewhat past said inlet port which is coaxial with said second rotor.

2. A single vane motor as defined in claim 1 including a swivel bearing means along the length of said longitudinal slot in sealing engagement respectively with the opposed faces of said vane.

3. A single vane motor as defined in claim 1 wherein said enclosed housing is comprised of a main portion providing said bore and a pair of opposed end plates removably fixed to the respective ends thereof.

4. A single vane motor as defined in claim 3 wherein bearing means are provided in said end plates to rotatably support said first and second rotors in fixed positions relative to each other.

5. A single vane motor as defined in claim 4 wherein the radius of said second rotor is such that the outer circumferential face thereof rotates in close proximity to said minor portion.

6. A single vane motor as defined in claim 1 including seal means along the outer edge of said vane.

7. A single vane motor as defined in claim 1 including seal means between the opposed outer edges of said drum and the inside face of said bore.

8. A single vane motor as defined in claim 5 including longitudinal seal means fixed within said bore between said inlet and exhaust ports. 

1. A single vane motor for work extraction from the expansion of compressible fluids comprising, A. an enclosed housing providing,
 1. an inner bore; B. a first rotor, rotatably mounted within said inner bore comprised of,
 1. an output shaft journaled in said housing and spanning said bore,
 2. a vane fixed to said output shaft, within said bore, and extending radially outwardly into close proximity to the inner walls of said housing; C. a second rotor in the form of an annular drum, rotatably mounted within said housing bore on an axis offset from and parallel to the first rotor axis and providing,
 1. a longitudinal through opening providing for passage therethrough of said output shaft,
 2. a longitudinal slot through the wall of said drum, providing for the radial extension therethrough of said vane and relative movement between said vane and drum,
 3. a depression having a predetermined size located closely upstream of the longitudinal slot; D. circumferentially spaced apart inlet and exhaust ports extending through the wall of said enclosed housing said bore provides an inner wall, the major portion of which is coaxial with said first rotor and a minor portion extending between said exhaust port and a line somewhat past said inlet port which is coaxial with said second rotor.
 2. a vane fixed to said output shaft, within said bore, and extending radially outwardly into close proximity to the inner walls of said housing; C. a second rotor in the form of an annular drum, rotatably mounted within said housing bore on an axis offset from and parallel to the first rotor axis and providing,
 2. a longitudinal slot through the wall of said drum, providing for the radial extension therethrough of said vane and relative movement between said vane and drum,
 2. A single vane motor as defined in claim 1 including a swivel bearing means along the length of said longitudinal slot in sealing engagement respectively with the opposed faces of said vane.
 3. A single vane motor as defined in claim 1 wherein said enclosed housing is comprised of a main portion providing said bore and a pair of opposed end plates removably fixed to the respective ends thereof.
 3. a depression having a predetermined size located closely upstream of the longitudinal slot; D. circumferentially spaced apart inlet and exhaust ports extending through the wall of said enclosed housing said bore provides an inner wall, the major portion of which is coaxial with said first rotor and a minor portion extending between said exhaust port and a line somewhat past said inlet port which is coaxial with said second rotor.
 4. A single vane motor as defined in claim 3 wherein bearing means are provided in said end plates to rotatably support said first and second rotors in fixed positions relative to each other.
 5. A single vane motor as defined in claim 4 wherein the radius of said second rotor is such that the outer circumferential face thereof rotates in close proximity to said minor portion.
 6. A single vane motor as defined in claim 1 including seal means along the outer edge of said vane.
 7. A single vane motor as defined in claim 1 including seal means between the opposed outer edges of said drum and the inside face of said bore.
 8. A single vane motor as defined in claim 5 including longitudinal seal means fixed within said bore between said inlet and exhaust ports. 